Bolt-anchor.



H. W. PLElSER.

BOU ANCHOR.

APPLICAUOH FILED .uM/4.1913.

1988,'7, Patented Da. 17,1918.

HENRY W. PLEISTER, OF WESTFIELD, NEW

NEWHALL, Jn., nxncu'ron or JERSEY, AssIGNoR To HENRY is.

HENRY B. NEWHALL, DECEASEI).

BOLT-ANCHOR.

Application filed May 4, 1918.

T 0 all whom it' may Concern Be it known that I, HENRY 1V. PLnIsTnR, a citizen of the United States, residing at lllesteld, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Bolt-Anchors, of which the following vis a specitLation, taken in connection with the accompanying drawings.

My invention relates to bolt anchors.

In the present form `of bolt anchors now on the market, the maximum expansion is approximately at the extreme inner end of the an hor. In practice 'this often is a serious detriment in that the screw or other expandingmember, having forced the bolt anchor out to its maximum expansion, binds and it is .impossible to bring the head of the bolt. up Hush with the work. This requires that the hole be enlarged, entailing additional labor and expense, or a diiferent size bolt anchoibe used.

By my present invention I not only ob tain a bolt anchor of greater exibility and lighter weight, thereby saving material, but also overcome 'the objection above noted, giving a longer surface of maximum contact or grip on the Lexterior of the bolt anchor, thereby insuring an increased fricytional hold, and distributing this maximum grip over a larger area.

Further, by my invention, in case the hole is drilled too tight, or not of quite the correct diameter to accommodate the full expansion of the bolt anhor, the highest set of ribs, at the inner end'of my bolt anchor, will more or less bend or collapse. This eases the torsional strain on the head of the bolt or screw and permits the bolt being screwed home without either jamming or having its head twisted ofi'.

My present 'bolt anchor l.gives greater ri- `.oddity of the bodv member or .shell 'where the axial bore tapers and where the expansion is produced.

My invention further relates to certain details of construction and conbinations which will be more fully hereinafter described and set forth in the appended claims.`

.l have shown in the yaccompanving drawing different illustrative' embodiments of invention, but of course it is to be understood that mv invention is not to be confined to the forms illustrated except as re- Specfication of Letters Patent.

Patented Dec. 17, 1918. Seria1No.'232,472.

quired by the scope of the appended claims. ln this drawing, the same reference numerals refer to similar parts in ythe several figures.

Figure 1 is a vertical section through a two-part bolt anchor, known as a two-part lag shield, embodying my invention.

Fig. 2 is a vertical section through the lag shield shown in Fig. 1, mounted in a support and cooperating with a lag screw and with the work to be supported.

F ig. y3 is a vertical section similar to Fig. 2, but lshowingthe vhole in the support drilled too tight to accommodate the full expansion Aof the bolt anchor without the bending or collapsing of the transverse ribs.

Fig. t is a vertical section through a onepart bolt anchor known in the trade as an anchor, s^rew anchor, or ductile anchor.

In the illustrative embodiments of my invention shown in the drawing, 1,-is a bolt anchor formed of the sections 2 and 3 which are secured together by 'the usual clamping lugs 4.. These two sections 2 and 3 form an expansion bolt anchor having a body portion or shell 5 of peculiar and distinctive congruration. The bolt anchor is provided with an open throat 6 which is the beginning of the axial bore 7.. That portion of the bore which is the open throat is substantiallv cvlindrcal. Adjacent to the open throat the axial bore 7 tapers toward the other end of the holt anchor to a point whi'h is its nearest approach to the axis of the bolt anchor. This point rnav varv between the ends of the anchor. Preferablv it is locnted at the point 8 which is some distance from the end 9. From this point 8 to the end 9 of the bolt anchor the aXial bore is substantiallv cylindrical.

The bodv portion or shell 5 graduallv increases in thickness from theend 11 of the bolt anchor to approximately the noint 12 which is adjacent to the point 8. From the point l2 the. portion 13 of *be bodv inerber or shell 5 is of uniform thickness. but Ynot as thick as the .shell is at the point 12.

ln the form illustrated I mount a series of transverse ribs 14. 14 of uniform height on one portion of the bolt anchor. and another series of transverse ribs 15, 15 of a different uniformheinht upon the other portion of the bodv member or shell. both series terminating in a uniform cylindrical exterior. Upon the collar I mount longitudinally extending ribs 16 which preferably extend slightly above the tops of the ribs 14: and 15.

By this form of bolt anchor having the peculiar contour of body member or shell 5 in combination with the series of ribs 111, 14 and 15, 15, together with the other features, I am enabled to make a bolt anchor of great flexibility and one of light weight, whereby the metal required in its manufacture is economized without impairing the strength of the bolt anchor.

In use a hole 17 is drilled in the support 18 of masonry, brick, terra cotta, tile or any other suitable material and the bolt anchor 1 is, placed therein, the work 19 being held to the face120 of the support by the lag screw 21.' When the sections 2 and 3 arecast the female screw threads 22 are cast in them at the-same time.

In those cases where a hole 23 is drilled inthe support 18 a little too tightV ory is too. small in diameter to accommodate the-full expansion of the bolt anchor, the high and weaker ribs 15, 15, will. bend or collapse as shown in Fig. 3 from the point 12 adjacent to the point 8 which is theV nearest approach of the' inclined axial bore 7 to the axis of the bolt anchor. One or more ofthe other transverse ribs 14 may also bend or collapse if the strain is suiliciently great. This permits my improved bolt anchor to be used in a hole which otherwise wouldhave to beredrilled or enlarged, or a different size bolt anchor would have to be used.

The maximum strain or grip is distributed by my bolt anchor from a point 19 to the inner end 9 ofthe bolt anchor. It is therefore impossible to twist olf the vhead of the lag screwv if the bolt anchor is used in a hole a little too small to accommodate its maximum expansion, but the body member or shell is also given greatk rigidity where the axial bore tapers and where the expansion is produced.

My invention may be kalso embodied in bolt anchors formed of some `ductile material as for example lead or an alloy in which the screw cuts its own coperating screw threads. I have shown in Fig. i a one piece bolt anchor 24 formed of lead or an alloy having a body member 25 and an inclined bore 26 and different sets of transverse ribs 115 and 114C and longitudinallyl extending ribs 116 all of which operate inthe same manner as the corresponding elements previously described in full.

Having thus described the invention in connection with dil'erentV illustrative em- CopiesV of this patent may beao'etainei for all of uniform height,l

bodiments thereof, to the details of which I do not desire to be limited, except as required by the scope 0f the appendedclaims.

What VI claim as my invention and desire to secure by Letters Patent is 1*- 1. In a bolt anchor the combination of an expansible member having a wall which gradually increases in thickness to a .point between its ends and from that point is of less and of uniform thickness to the'end of the bolt anchor.

2. In a bolt anchor the combination of an expansible member having a wall which gradually increases in thickness to a .point between its ends and from that point is of less and of uniform thickness to the end of the bolt anchor and exterior transverse ribs of uniform height on the respective exterior portions of the bolt anchor.

3. In a bolt anchor, the combination of yan expansible member having .an axiali bore tapering .from near oneendto a point intermediate the ends-of the anchorand lfrom that kpoint being of substantially uniform diameter, the body of the vexpansible member having a wall which gradually increases in thickness to a point ybetween the ends of the anchor and from that'point is of less and of uniform thickness to the end of the bolt anchor. Y

Ll., In a bolt anchor, the combination ofan expansible member having an axial bore tapering termediate the ends of the anchor and from that point being of substantially.uniform diameter, the body of the expansible mem-l ber having a Wall which gradually increases in thickness to a point between the ends .of the anchor, and from that point is of less and of uniform thickness to the end of the bolt anchor, and .exterior of uniform height on the respective exterior portions of the bolt anchor.V

5. In a bolt anchor the combination of an expansible member having an Vaxial bore tapering from near one end to a point intermediate the ends of the anchor andfrom that point being of substantially uniform diameter, the body ofthe anchor having ya wall which increases in thickness approximately throughout the length of the tapering axial bore, said wall froml that point being of less and of uniform thickness lto the end of the bolt anchor, and two sets of transverse ribs of diderent height on the exterior of the bolt anchor the ribs in each set being of the same height.

HENRY W. PLEISTER.

Witnesses:

MARY R. RYAN, A.k M. WILLIAMS.

five cents each, by addressing' the Commissioner or Patents.

Washington, D. G.

from near one end to a point in-l transverse ribs 

